Core research will continue to focus on the implementation and application of an integrating transient recorder (ITR) which will be used for Time Array Detection (TAD) in time=of-flight (TOF) mass spectrometry to make it possible to detect and integrate all the ion current (over the complete mass range) accelerated from the ion source of this instrument. This capability is expected to increase the full spectrum sensitivity of the instrument by at least an order of magnitude and increase the rate of acquiring useable spectra by an order of magnitude. Both of these features will have a profound effect on conventional GC-MS, especially with increasing emphasis on the use of capillary columns in the analysis of complex mixtures found in most biological samples. An existing TOF instrument has bee" modified with a continuous source and an electric sector to filter out ions with aberrant energy. Energy filtering and beam pulsing of a continuous source substantially increases the resolving power of the TOF instrument. Investigations into the mechanism of thermally assisted FAB will continue as this novel desorption ionization technique is applied to the analysis of peptides, bile acids, porphyrins, and other biologically important molecules. Collaborative research will emphasize extension of metabolic profiling methodology for organic acids and steroids in urine for investigations of altered metabolism in human disease states such as diabetes and of the physiological response to xenobiotics such as pollutants and drugs. Requests for service and collaboration will call for analyses of physiological fluids and other biochemical samples for carboxylic acids, sugars, indole derivatives, etc. Many projects involving organic synthesis will continue to require exact measurements to validate the empirical formulas of their products. Training will continue to be an important feature in the Facility program; approximately 20 graduate students receive detailed training in mass spectrometry through research projects with the five professional investigators in the Facility program.